Summary:

Tsurumi Asuta is a 17-year-old second year high school student. He was an apprentice cook working at the public diner "Tsurumi-ya" that was managed by his father. One day, Tsurumi-ya is hit by fire and Asuta dived inside the burning shop in order to save his father's santoku knife which is said to be his father soul, where he found demise.
When he came to, he was in the midst of a strange jungle. He was then attacked by a beast resembling a boar, but Asuta was saved by a girl named Ai Fa claiming herself as part of the "People of Morihen." It was then that he realized he was in another world.